How do I repair roof flashing?

[wilsarnie]

I have a damp spot in the corner of my bathroom ceiling where mould has started to grow.

Above is a pitched roof. I can see a gap in the step flashing against a small dividing wall between my roof and the neighbours.

Can I repair this gap in the flashing with silicon caulk sealant? Is this easy? (I can reach the flashing easily by ladder as is ground floor)

I am a relatively new DIY'er but willing to try new tasks!! Or should I just cut my losses and call in the roof contractor....?

[buildersmate]

Can't quite visualise the way you describe where the gap is - hence not sure if its because something has dropped off, or just opened up. Also not sure if its lead flashing or some other material. Either way its worth having a go yourself because it doesn't sound like anything can get fouled up worse, and it might solve the problem and save you a lot - contractor's don't like little jobs like this - not cost-effective for them. Two materials to suggest - the silicon caulk you refer to - there is a special version in grey sold as a flashing bedding compound. It seems to contain silicon (as it smells of vinegar the same), but is a good colour and probably contains additives to resist the elements. Wickes sell it or try a Builders Merchant. About �6. If its a patch you need, there are reels of aluminium flashing with black bitumen stuck to the back. These are self-adhesive and can be used to cover cracks. Obviously clean the surrounding area well with white spirit before applying either. Good luck.

[wilsarnie]

Thanks so much buildersmate, I'm going to try it this weekend.

I've tried to find pics of the kind of flashing I mean but can't find any! Should really take one myself.

It kind of looks like 17 on this pic...

http://www.a-lineroofing.com/roofingterms.ivnu

...but it's not a chimney but a 12 inch high dividing wall between my pitched roof and the neighbours'.

I can see a gap between the flashing and the brick wall, just like it's come away, about half inch. Enough to let rain in though isn't it?!

I'll try the caulk then if all else fails just whack a bit of tape on it and see if that helps!

Thanks